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Our purpose in this study was to analyze perceptual and cardiovascular responses in low-load resistance training (RT) sessions associated with a fixed non-elastic band compressed to the proximal region of the arms (p-BFR) versus a pneumatic cuff inflated to a pressure of 150 mmHg (t-BFR). Participants (16 healthy trained men) were randomly assigned to two conditions of low-load RT (20% one repetition maximum [1RM]) with BFR (p-BFR or t-BFR). In both conditions, the participants performed five exercises (4 sets/30-15-15-15) for the upper-limbs, but in one of the conditions, the exercises were performed with a p-BFR induced by a non-elastic band, while in the other, the exercises were performed with a t-BFR using a device with similar width. The devices used to generate the BFR had similar widths (5 cm). Brachial blood pressure (bBP) and heart rate (HR) were measured before, after each exercise and after the experimental session (5-, 10-, 15-, and 20 min post-session). Rating of perceived exertion (RPE) and rating of pain perception (RPP) were reported after each exercise and 15 minutes post-session. HR increased during the training session in both conditions, with no differences between p-BFR and t-BFR. Neither intervention increased diastolic BP (DBP) during training, but there was a significant post-session reduction in DBP in the p-BFR, with no differences observed between conditions. There were no significant differences in RPE and RPP in the two training conditions, with both conditions associated with higher RPE and RPP at the end versus beginning of the experimental session. We conclude that when BFR device width and material are similar, low-load training with t-BFR and p-BFR promotes similar acute perceptual and cardiovascular responses in healthy trained men. [ABSTRACT FROM AUTHOR]

Purpose: The association between racial discrimination and subclinical cardiovascular markers remains under-examined. We aimed to investigate the association of race/skin color and racial discrimination with pulse wave velocity (PWV) and carotid intima-media thickness (c-IMT) in the Brazilian context.Methods: We used data from 13,284 participants from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) baseline with information of PWV and 9850 for c-IMT. Self-reported race/skin color and perceived racial discrimination were the exposures. PWV and c-IMT were used continuously and categorizing according to cutoff that indicates increased cardiovascular risk. Linear and logistic regression models were used.Results: Experience of racial discrimination was reported by 7% of total participants, but this prevalence was much higher among Blacks than Browns (PWV sample: 31,9% vs. 6,1%; c-IMT sample: 33,7% vs. 6,8%). After adjustments for age, sex, and research center, Blacks and Browns presented higher means of PWV and c-IMT and had greater chances of PWV>10 m/s and c-IMT≥75th percentile than Whites. The magnitude of all these associations were higher among Blacks and Browns with racial discrimination. In final models adjusted for education this pattern of association remained the same, although an attenuation in the magnitude of the association has been observed.Conclusions: Blacks and Browns presented worse profiles of subclinical cardiovascular markers compared to Whites and those exposed to racial discrimination seem to have an additional cardiovascular risk. [ABSTRACT FROM AUTHOR]

We investigated the effects of a recreational training (RET) protocol in elderly women with type-2 diabetes mellitus (T2DM). We hypothesized that non-conventional physical activities of RET protocol might improve clinical outcomes regarding cardiovascular function, metabolic profile and mental health as participants keep the adherence to the protocol during the 3-month follow-up. Cardiovascular parameters (heart rate, systolic and diastolic blood pressure), circulating biomarkers (glucose and lipids) and salivary cortisol were attenuated in response to exercise. RET also reduced anxiety and depression indexes. RET protocol constitutes a potential therapeutic approach for managing T2DM in elderly women. [ABSTRACT FROM AUTHOR]

Ethnicity is an important determinant of blood pressure levels, being black individuals affected more than any other ethnic group. Arterial stiffening, an independent risk factor for hypertension, is also influenced by ethnicity. However, whether black individuals from different continents would have different patterns of arterial stiffening is still unknown. Thus, the authors aimed to compare pulse wave velocity (PWV) in black subjects living in Angola and Brazil. A total of 677 black individuals from two independent cross-sectional studies conducted in Brazil and Angola were included in this analysis. Carotid-to-femoral PWV was measured following the same protocols for both studies, as well as clinical and anthropometric variables. Adjusted PWV was higher in Brazilian blacks than in Angolans, regardless of sex (men from Brazil: 10.7 ± 1.8 vs men from Angola: 9.9 ± 1.8 m/s, P < .001; women from Brazil: 10.3 ± 1.5 vs women from Angola: 9.2 ± 1.3 m/s, P < .001). Although the cf-PWV was higher in Brazilian blacks, the age-related increase in cf-PWV was higher in Angolan men compared to Brazilians, but not in women. SBP showed the strongest association with cf-PWV, regardless of sex and country. However, age was associated with cf-PWV in all groups, except in Brazilian men. Our results clearly show a difference in PWV between two black populations, and highlight for sex differences in the hemodynamic parameters that might affect blood pressure levels in these populations. [ABSTRACT FROM AUTHOR]

The present study aims to evaluate the level of stress recovery and cardiovascular performance in Brazilian Jiu-Jitsu athletes. In addition to investigating the relationship between recovery and stress indicators with cardiovascular parameters. The sample included athletes of various ages, five academies in the city of Aracaju - Sergipe - Brazil, during the pre-competitive phase. The level of recovery and stress of the athletes was evaluated by the questionnaire Recovery and Stress (RESTQ-Sports). To evaluate the cardiovascular performance, the Cooper test of 12 minutes was used on the track. Descriptive statistics were used, with mean and standard deviation. Spearman's correlation was used among the variables of recovery, stress and cardiovascular performance (p <0.05). Through the evaluation of the level of recovery of stress, it was possible to verify that the behavior of stress (total stress = 2,56) is in balance with the capacity of recovery (total recovery = 2.78). In addition to the resting heart rate (HRR) and the final heart rate (FHR) achieved in the Cooper test, it was positively correlated with the sports stress status (p <0.05). It was concluded that there is a balance between stress and recovery level of athletes in general and specific indicators. In addition, the sports stress indicator can modulate both FCR and FCF. [ABSTRACT FROM AUTHOR]

Highlights • Children and adolescents with myelomeningocele showed higher heart rate at rest. • Children and adolescents with myelomeningocele did not show differences in HR and BP variability. • Children and adolescents with myelomeningocele showed lower baroreflex sensitivity. Abstract Background Cardiovascular autonomic dysfunction is associated with the development of cardiovascular diseases, but little is known about it in children and adolescents with myelomeningocele. Objective This study investigated the cardiovascular autonomic function in wheelchair-using children and adolescents with myelomeningocele. Methods Twenty-two participants were assigned to one of two groups: myelomeningocele group (n = 11) and Control group (n = 11). Heart rate variability and systolic blood pressure variability were collected in supine resting position using spectral analyses. Spontaneous baroreflex sensitivity was collected by time-domain through the sequence method. Results At rest, heart rate was higher in myelomeningocele group when compared to Control group (mean difference 22.1, 95% CI 4.82–39.40; p = 0.01). The heart rate and systolic blood pressure variability parameters did not show differences between groups. However, myelomeningocele showed lower gain mean in baroreflex sensitivity (mean difference −4.5, 95% CI −8.47 to −0.60; p = 0.02), when compared to Control. Conclusion Wheelchair-using children and adolescents with myelomeningocele presented differences in the autonomic cardiovascular function. This may be associated with hypomobility due to wheelchair dependence, and venous muscle pump insufficiency due to paraplegia. [ABSTRACT FROM AUTHOR]

Background: Resistant hypertension (RH) treatment requires an adequate and intense therapeutic approach. However, the results are not always satisfactory despite intensive treatment. Of the different pathophysiological mechanisms involved in the pathogenesis of RH, sympathetic overstimulation and therapies that block the sympathetic system have been widely studied. These approaches, however, are invasive and expensive. Another possible approach is by transcutaneous electrical nerve stimulation (TENS), a noninvasive method that modulates activity by using low-frequency transcutaneous electrical stimulation to inhibit primary afferent pathways. Thus, the current study will evaluate the effect of applying TENS in the cervicothoracic region of subjects with RH and will seek to develop a new low-cost and readily available therapy to treat this group of hypertensive individuals.Methods/design: This is a randomized, single blind (subject), parallel-assignment study controlled with a sham group and including participants aged 40 to 70 years with resistant hypertension. The trial has two arms: the treatment and control (sham group). The treatment group will be submitted to the stimulation procedure (TENS). The sham group will not be submitted to stimulation. The primary outcomes will be a reduction in the peripheral blood pressure and adverse events. The secondary outcomes will be a reduction the central blood pressure. The study will last 30 days. The sample size was calculated assuming an alpha error of 5 % to reject the null hypothesis with a statistical power of 80 %, thereby resulting in 28 participants per group (intervention versus sham).Discussion: In recent decades, RH has become very common and costly. Adequate control requires several drugs, and in many cases, treatment is not successful. Sympathetic nervous system inhibition by renal denervation and central inhibition have significant effects in reducing BP; however, these treatments are costly and invasive. Another type of sympathetic nervous system inhibition can also be noninvasively achieved by electric current. Therefore, the application of TENS may be a new therapeutic option for treating resistant hypertensive individuals.Trial Registration: Clinical Trials NCT02365974. [ABSTRACT FROM AUTHOR]

The heart rate variability (HRV) and surface electromyography (sEMG) are important tools in the evaluation of cardiac autonomic system and neuromuscular parameters, respectively. The aim of the study was to evaluate the behavior of HRV and sEMG of the vastus lateralis in two exercise protocols on a cycle ergometer at 60 and 80 rpm. Eight healthy men cyclists who have trained for at least two years were evaluated. Reduction was observed followed by stabilization of RMSSD and SDNN indices of HRV (p<0.05) along with increases in the amplitude of the sEMG signal (p<0.05) in both protocols. Significant correlations were observed between the responses of HRV and sEMG in the cadence of 60 rpm (RMSSD and sEMG: r = -0.42, p=0.03; SDNN and sEMG: r = -0.45, p=0.01) and 80 rpm (RMSSD and sEMG: r = -0.47, p=0.02; SDNN and sEMG: r = -0.49, p=0.01), yet no difference was observed for these variables between the two protocols. We concluded that the parasympathetic cardiac responses and sEMG are independent of cadences applied at the same power output. [ABSTRACT FROM AUTHOR]

Background: Music has been proven to promote changes in cardiac autonomic modulation. However, it is not clear whether the effects of the auditory stimulation on heart rate variability (HRV) are dependent on its intensity.Objective: The study intended to investigate the acute effects on the geometric HRV indices of auditory stimulation with heavy metal and baroque music using different intensities of auditory stimulation.Design: The study was a nonrandomized, clinical trial.Setting: The study was conducted at the facility of the Faculty of Sciences of the São Paulo State University, on the campus in Marilia, Brazil.Participants: Participants were 24 healthy women aged between 18 and 27 y.Intervention: HRV was recorded for each participant for 10 min at rest. Subsequently, participants were exposed to baroque or heavy metal music through an earphone. They were exposed to 3 equivalent sound levels-60-70 decibels (dB), 70-80 dB, and 80-90 dB-for 5 min in each intensity range. After the first session of baroque or heavy metal music, participants rested for an additional 5 min. Then they were exposed to the other musical style. The first style played for each musical period was randomly selected for all individuals and then the other style would be played automatically for the second session.Outcome Measures: The HRV analysis was performed using the following geometrical methods: (1) the triangular index (RRtri), (2) the triangular interpolation of the RR interval histogram (TINN), and (3) the Poincaré plot, using SD1-the standard deviation of the instantaneous variability of the beat-to beat heart rate (HR), SD2-the standard deviation of the long-term, continuous, RR interval variability, and the SD1/SD2 ratio-the ratio between the short- and long-term variations among the RR intervals.Results: The classic baroque music by Johann Pachelbel, "Canon in D Major," did not induce significant changes in the geometric indices of HRV at 60-70 dB, 70-80 dB, or 80-90 dB. However, auditory stimulation with heavy metal music, using "Heavy Metal Universe" by Gamma Ray, decreased the RRtri, TINN, and SD2 at 2 specific sound pressures (60-70 dB and 80-90 dB).Conclusions: Auditory stimulation with the selected baroque music did not alter cardiac autonomic modulation, but the selected, heavy metal style of music in the lower and higher intensities reduced the global component of HRV acutely. [ABSTRACT FROM AUTHOR]

This study aimed to compare the acute cardiovascular responses during and after resistance exercise with and without whole-body vibration. Nineteen sedentary adults randomly performed one session of isometric squats without vibration and the same exercise with vibration. Systolic (SBP) and diastolic blood pressure (DBP), heart rate (HR), stroke volume (SV), cardiac output (CO) and systemic vascular resistance (SVR) were measured. SBP, DBP and HR were also measured for 20 min after the sessions. The exercise with vibration demonstrated significant values ​​(P< 0.05) for SBP (second to sixth sets), DBP (third to sixth sets) and SVR (second to sixth sets) compared with the exercise without vibration. After the sessions, the values ​​of SBP for both exercises were significantly lower than the respective resting values; with no difference between the sessions. In conclusion, exercise with vibration caused increases in SBP, DBP and SVR compared with exercise with no vibration in sedentary adults. [ABSTRACT FROM PUBLISHER]

Objective: To verify whether 30 minutes of rest between two incremental shuttle walking tests (ISWT) are enough for cardiovascular variables and perceived exertion to return to baseline values in healthy subjects in a broad age range. Method: The maximal exercise capacity of 334 apparently healthy subjects (age ≥18) was evaluated using the ISWT. The test was performed twice with 30 minutes of rest in between. Heart rate (HR), arterial blood pressure (ABP), dyspnea, and leg fatigue were evaluated before and after each test. Subjects were allocated to 6 groups according to their age: G1: 18-29 years; G2: 30-39 years; G3: 40-49 years; G4: 50-59 years; G5: 60-69 years and G6: ≥70 years. Results: All groups had a good performance in the ISWT (median >90% of the predicted distance). The initial HR (HRi) of the second ISWT was higher than the first ISWT in the total sample (p<0.0001), as well as in all groups (p<0.0001). No difference was observed in the behavior of ABP (systolic and diastolic) and dyspnea between the two tests, but this difference occurred for leg fatigue (greater before the second ISWT) in G1 (p<0.05). Most subjects (58%) performed better in the second test. Conclusion: 30 minutes of rest between two ISWTs are not enough for all cardiovascular variables and perceived exertion to return to baseline values. However, this period appears to be sufficient for blood pressure and performance to recover in most subjects. [ABSTRACT FROM AUTHOR]

Platonia insignis Mart. (Clusiaceae) is a medicinal plant from the Brazilian Amazon region. The present study evaluated the biological potential of the ethanol extract ( Pi-EtOH) and ethyl acetate fraction ( Pi-EtOAc) of the P. insignis fruit shells on the cardiovascular system of rats. Pi-EtOH or Pi-EtOAc (12.5, 25, and 50 mg/kg) was administered intravenously in normotensive rats (260-300 g), and the mean arterial pressure and the heart rate were monitored. The Pi-EtOH induced hypotension (−11.56±0.89, −7.43±0.85, and −17.56±1.97 mmHg) followed by bradycardia in two highest doses (−8.89±3.62 and −15.79±1.83 beats/min) and Pi-EtOAc, at the same doses, induced hypotension (−11.2±1.03, −14.48±1.13, −29.89±2.67 mmHg) more intensively, followed by tachycardia at the dose 12.5 and 25 mg/kg (15.64±2.06, 19.31±1.92 beats/min) and bradycardia at a dose of 50 mg/kg (−9.98±7.33 beats/min). The hypotensive response from Pi-EtOAc was not attenuated when used in the pretreatment with L-NAME, verapamil, propranolol, and hexamethonium. However, when using yohimbine, the hypotensive effect was inhibited (−4.42±1.28 ( P<.05), −3.29±0.99 ( P<.05), 2.06±1.18 mmHg ( P<.05); Student's t-test). Hence, the Pi-EtOAc seems to act similarly to the α2-adrenergic agonist in this hypotensive effect. [ABSTRACT FROM AUTHOR]

Experiments were performed to determine the influence of exercise training by swimming on cardiovascular autonomic control and renal morphology in spontaneously hypertensive rats (SHR) and Wystar-Kyoto (WKY) rats. Sedentary normotensive (SN), trained normotensive (TN), sedentary hypertensive (SH), and trained hypertensive (TH) rats were included in this study. Arterial pressure (AP), heart rate (HR), means of power spectral analysis of HR (HRV) and systolic AP variability (SAPV) were recorded in baseline conditions. Following, the HR baroreflex and autonomic tonus control were assessed. At the end, all animals were euthanized and their kidneys were excised to evaluate renal damage. Resting bradycardia was observed in TH and TN rats compared with their respective sedentary animals (p < 0.05). Exercise training attenuated AP in TH vs. SH (p < 0.001). The LF component of HRV and SAPV were lower in TH than SH (p < 0.05). The LF/HF relation was lower in TH than SH and SN (p < 0.05). TN and TH rats showed a sympathetic tonus reduction in comparison to SN and SH rats (p < 0.001). The TH presented an increased vagal tonus compared to SH (p < 0.05). Exercise training improved baroreflex control of HR in TH group versus SH (p < 0.05). The TH showed a lower number of sclerotic glomeruli compared to SH (p < 0.005). The exercise training decreases the glomerular indexes in TN and TH (p < 0.05). Further analysis showed a significant correlation between sympathetic nervous activity and AP levels (p < 0.05). A positive association was also found between sympathetic nervous activity and glomerular index (p < 0.05). Therefore, the exercise training reduces AP and attenuates renal damage. In addition, the attenuation of renal injury was associated with lower sympathetic activity. These findings strongly suggest that exercise training may be a therapeutic tool for improving structure and renal function in hypertensive individuals. [ABSTRACT FROM AUTHOR]